EP0145980A2 - Process for the preparation of pure carboxylic acids - Google Patents
Process for the preparation of pure carboxylic acids Download PDFInfo
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- EP0145980A2 EP0145980A2 EP84113889A EP84113889A EP0145980A2 EP 0145980 A2 EP0145980 A2 EP 0145980A2 EP 84113889 A EP84113889 A EP 84113889A EP 84113889 A EP84113889 A EP 84113889A EP 0145980 A2 EP0145980 A2 EP 0145980A2
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- EP
- European Patent Office
- Prior art keywords
- cobalt
- acids
- reaction solution
- acid
- carboxylic acids
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
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- 150000001735 carboxylic acids Chemical class 0.000 title claims abstract description 13
- 238000000034 method Methods 0.000 title claims description 13
- 238000002360 preparation method Methods 0.000 title claims description 7
- 239000010941 cobalt Substances 0.000 claims abstract description 36
- 229910017052 cobalt Inorganic materials 0.000 claims abstract description 36
- 238000006243 chemical reaction Methods 0.000 claims abstract description 29
- 239000003054 catalyst Substances 0.000 claims abstract description 24
- GUTLYIVDDKVIGB-UHFFFAOYSA-N cobalt atom Chemical compound [Co] GUTLYIVDDKVIGB-UHFFFAOYSA-N 0.000 claims abstract description 22
- 239000002253 acid Substances 0.000 claims abstract description 20
- 150000001991 dicarboxylic acids Chemical class 0.000 claims abstract description 6
- 150000002763 monocarboxylic acids Chemical class 0.000 claims abstract description 6
- 239000003795 chemical substances by application Substances 0.000 claims abstract description 5
- 230000020477 pH reduction Effects 0.000 claims abstract description 5
- 238000006386 neutralization reaction Methods 0.000 claims abstract description 4
- 239000000243 solution Substances 0.000 claims description 27
- 239000008346 aqueous phase Substances 0.000 claims description 9
- 239000012074 organic phase Substances 0.000 claims description 8
- 125000004432 carbon atom Chemical group C* 0.000 claims description 6
- 150000001868 cobalt Chemical class 0.000 claims description 6
- 238000004519 manufacturing process Methods 0.000 claims description 6
- 239000007864 aqueous solution Substances 0.000 claims description 5
- 230000006315 carbonylation Effects 0.000 abstract description 5
- 238000005810 carbonylation reaction Methods 0.000 abstract description 5
- 150000003839 salts Chemical class 0.000 abstract description 5
- 150000007513 acids Chemical class 0.000 description 14
- MUBZPKHOEPUJKR-UHFFFAOYSA-N Oxalic acid Chemical compound OC(=O)C(O)=O MUBZPKHOEPUJKR-UHFFFAOYSA-N 0.000 description 13
- 239000000047 product Substances 0.000 description 10
- 150000001732 carboxylic acid derivatives Chemical class 0.000 description 8
- CBQJSKKFNMDLON-UHFFFAOYSA-N N-acetylphenylalanine Chemical compound CC(=O)NC(C(O)=O)CC1=CC=CC=C1 CBQJSKKFNMDLON-UHFFFAOYSA-N 0.000 description 7
- KJNSHVJSFPXZRZ-UHFFFAOYSA-N acetylcarbamic acid Chemical class CC(=O)NC(O)=O KJNSHVJSFPXZRZ-UHFFFAOYSA-N 0.000 description 7
- HEMHJVSKTPXQMS-UHFFFAOYSA-M Sodium hydroxide Chemical compound [OH-].[Na+] HEMHJVSKTPXQMS-UHFFFAOYSA-M 0.000 description 6
- VEXZGXHMUGYJMC-UHFFFAOYSA-N Hydrochloric acid Chemical compound Cl VEXZGXHMUGYJMC-UHFFFAOYSA-N 0.000 description 5
- OFOBLEOULBTSOW-UHFFFAOYSA-N Malonic acid Chemical compound OC(=O)CC(O)=O OFOBLEOULBTSOW-UHFFFAOYSA-N 0.000 description 4
- CBQJSKKFNMDLON-JTQLQIEISA-N N-acetyl-L-phenylalanine Chemical compound CC(=O)N[C@H](C(O)=O)CC1=CC=CC=C1 CBQJSKKFNMDLON-JTQLQIEISA-N 0.000 description 4
- QAOWNCQODCNURD-UHFFFAOYSA-N Sulfuric acid Chemical compound OS(O)(=O)=O QAOWNCQODCNURD-UHFFFAOYSA-N 0.000 description 4
- 238000001914 filtration Methods 0.000 description 4
- 229910052500 inorganic mineral Inorganic materials 0.000 description 4
- BDAGIHXWWSANSR-UHFFFAOYSA-N methanoic acid Natural products OC=O BDAGIHXWWSANSR-UHFFFAOYSA-N 0.000 description 4
- 239000011707 mineral Substances 0.000 description 4
- 235000010755 mineral Nutrition 0.000 description 4
- 235000006408 oxalic acid Nutrition 0.000 description 4
- 238000000926 separation method Methods 0.000 description 4
- NTIZESTWPVYFNL-UHFFFAOYSA-N Methyl isobutyl ketone Chemical compound CC(C)CC(C)=O NTIZESTWPVYFNL-UHFFFAOYSA-N 0.000 description 3
- UIHCLUNTQKBZGK-UHFFFAOYSA-N Methyl isobutyl ketone Natural products CCC(C)C(C)=O UIHCLUNTQKBZGK-UHFFFAOYSA-N 0.000 description 3
- KWYUFKZDYYNOTN-UHFFFAOYSA-M Potassium hydroxide Chemical compound [OH-].[K+] KWYUFKZDYYNOTN-UHFFFAOYSA-M 0.000 description 3
- 238000001816 cooling Methods 0.000 description 3
- 238000001035 drying Methods 0.000 description 3
- 239000000203 mixture Substances 0.000 description 3
- 238000001556 precipitation Methods 0.000 description 3
- 239000002904 solvent Substances 0.000 description 3
- OSWFIVFLDKOXQC-UHFFFAOYSA-N 4-(3-methoxyphenyl)aniline Chemical compound COC1=CC=CC(C=2C=CC(N)=CC=2)=C1 OSWFIVFLDKOXQC-UHFFFAOYSA-N 0.000 description 2
- DLFVBJFMPXGRIB-UHFFFAOYSA-N Acetamide Chemical compound CC(N)=O DLFVBJFMPXGRIB-UHFFFAOYSA-N 0.000 description 2
- NBIIXXVUZAFLBC-UHFFFAOYSA-N Phosphoric acid Chemical compound OP(O)(O)=O NBIIXXVUZAFLBC-UHFFFAOYSA-N 0.000 description 2
- CDBYLPFSWZWCQE-UHFFFAOYSA-L Sodium Carbonate Chemical compound [Na+].[Na+].[O-]C([O-])=O CDBYLPFSWZWCQE-UHFFFAOYSA-L 0.000 description 2
- UIIMBOGNXHQVGW-UHFFFAOYSA-M Sodium bicarbonate Chemical compound [Na+].OC([O-])=O UIIMBOGNXHQVGW-UHFFFAOYSA-M 0.000 description 2
- 239000002585 base Substances 0.000 description 2
- 239000006227 byproduct Substances 0.000 description 2
- -1 cobalt carbonyl compounds Chemical class 0.000 description 2
- MQIKJSYMMJWAMP-UHFFFAOYSA-N dicobalt octacarbonyl Chemical group [Co+2].[Co+2].[O+]#[C-].[O+]#[C-].[O+]#[C-].[O+]#[C-].[O+]#[C-].[O+]#[C-].[O+]#[C-].[O+]#[C-] MQIKJSYMMJWAMP-UHFFFAOYSA-N 0.000 description 2
- 235000019253 formic acid Nutrition 0.000 description 2
- 229910052739 hydrogen Inorganic materials 0.000 description 2
- BTNMPGBKDVTSJY-UHFFFAOYSA-N keto-phenylpyruvic acid Chemical compound OC(=O)C(=O)CC1=CC=CC=C1 BTNMPGBKDVTSJY-UHFFFAOYSA-N 0.000 description 2
- 150000002762 monocarboxylic acid derivatives Chemical class 0.000 description 2
- 239000012071 phase Substances 0.000 description 2
- BWHMMNNQKKPAPP-UHFFFAOYSA-L potassium carbonate Chemical compound [K+].[K+].[O-]C([O-])=O BWHMMNNQKKPAPP-UHFFFAOYSA-L 0.000 description 2
- 229920006395 saturated elastomer Polymers 0.000 description 2
- 239000000126 substance Substances 0.000 description 2
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 description 2
- 239000001903 2-oxo-3-phenylpropanoic acid Substances 0.000 description 1
- WLJVXDMOQOGPHL-PPJXEINESA-N 2-phenylacetic acid Chemical compound O[14C](=O)CC1=CC=CC=C1 WLJVXDMOQOGPHL-PPJXEINESA-N 0.000 description 1
- UGFAIRIUMAVXCW-UHFFFAOYSA-N Carbon monoxide Chemical compound [O+]#[C-] UGFAIRIUMAVXCW-UHFFFAOYSA-N 0.000 description 1
- UFHFLCQGNIYNRP-UHFFFAOYSA-N Hydrogen Chemical compound [H][H] UFHFLCQGNIYNRP-UHFFFAOYSA-N 0.000 description 1
- UIIMBOGNXHQVGW-DEQYMQKBSA-M Sodium bicarbonate-14C Chemical compound [Na+].O[14C]([O-])=O UIIMBOGNXHQVGW-DEQYMQKBSA-M 0.000 description 1
- 238000010521 absorption reaction Methods 0.000 description 1
- 125000000738 acetamido group Chemical group [H]C([H])([H])C(=O)N([H])[*] 0.000 description 1
- 229910000288 alkali metal carbonate Inorganic materials 0.000 description 1
- 150000008041 alkali metal carbonates Chemical class 0.000 description 1
- 150000008044 alkali metal hydroxides Chemical class 0.000 description 1
- DEDGUGJNLNLJSR-UHFFFAOYSA-N alpha-hydroxycinnamic acid Natural products OC(=O)C(O)=CC1=CC=CC=C1 DEDGUGJNLNLJSR-UHFFFAOYSA-N 0.000 description 1
- 229910000147 aluminium phosphate Inorganic materials 0.000 description 1
- 150000001408 amides Chemical class 0.000 description 1
- KCXMKQUNVWSEMD-UHFFFAOYSA-N benzyl chloride Chemical compound ClCC1=CC=CC=C1 KCXMKQUNVWSEMD-UHFFFAOYSA-N 0.000 description 1
- 229940073608 benzyl chloride Drugs 0.000 description 1
- 230000015572 biosynthetic process Effects 0.000 description 1
- AXCZMVOFGPJBDE-UHFFFAOYSA-L calcium dihydroxide Chemical compound [OH-].[OH-].[Ca+2] AXCZMVOFGPJBDE-UHFFFAOYSA-L 0.000 description 1
- 239000000920 calcium hydroxide Substances 0.000 description 1
- 229910001861 calcium hydroxide Inorganic materials 0.000 description 1
- 229910002091 carbon monoxide Inorganic materials 0.000 description 1
- 125000002915 carbonyl group Chemical group [*:2]C([*:1])=O 0.000 description 1
- 150000001805 chlorine compounds Chemical class 0.000 description 1
- 150000001869 cobalt compounds Chemical class 0.000 description 1
- MULYSYXKGICWJF-UHFFFAOYSA-L cobalt(2+);oxalate Chemical compound [Co+2].[O-]C(=O)C([O-])=O MULYSYXKGICWJF-UHFFFAOYSA-L 0.000 description 1
- PFQLIVQUKOIJJD-UHFFFAOYSA-L cobalt(ii) formate Chemical compound [Co+2].[O-]C=O.[O-]C=O PFQLIVQUKOIJJD-UHFFFAOYSA-L 0.000 description 1
- 239000000356 contaminant Substances 0.000 description 1
- 238000004821 distillation Methods 0.000 description 1
- 230000002255 enzymatic effect Effects 0.000 description 1
- 150000002148 esters Chemical class 0.000 description 1
- 239000000706 filtrate Substances 0.000 description 1
- 150000004820 halides Chemical class 0.000 description 1
- 239000001257 hydrogen Substances 0.000 description 1
- 239000007788 liquid Substances 0.000 description 1
- 150000007524 organic acids Chemical class 0.000 description 1
- 229910000027 potassium carbonate Inorganic materials 0.000 description 1
- 239000002244 precipitate Substances 0.000 description 1
- 238000000746 purification Methods 0.000 description 1
- 239000002994 raw material Substances 0.000 description 1
- 239000011541 reaction mixture Substances 0.000 description 1
- 229910000030 sodium bicarbonate Inorganic materials 0.000 description 1
- 235000017557 sodium bicarbonate Nutrition 0.000 description 1
- 229910000029 sodium carbonate Inorganic materials 0.000 description 1
- 239000007787 solid Substances 0.000 description 1
- 239000007858 starting material Substances 0.000 description 1
- 239000000725 suspension Substances 0.000 description 1
Classifications
-
- C—CHEMISTRY; METALLURGY
- C07—ORGANIC CHEMISTRY
- C07C—ACYCLIC OR CARBOCYCLIC COMPOUNDS
- C07C231/00—Preparation of carboxylic acid amides
- C07C231/22—Separation; Purification; Stabilisation; Use of additives
- C07C231/24—Separation; Purification
Definitions
- the invention relates to a process for the pure preparation of carboxylic acids from their reaction solutions, in which cobalt carbonyl catalysts such as in particular Co 2 (CO) 8 or corresponding ionic cobalt carbonyl compounds are contained.
- cobalt carbonyl catalysts such as in particular Co 2 (CO) 8 or corresponding ionic cobalt carbonyl compounds are contained.
- cobalt carbonyl catalysts contain the valuable raw material cobalt, which should be recovered if possible.
- the cobalt catalysts complicate the purification of the carboxylic acids and form contaminants in the target products.
- a number of carboxylic acids can be prepared by inserting one or possibly two molecules of CO and possibly other parts of the molecule, such as arylacetic acids, especially phenylacetic acid, malonic acid and their esters, Phenylpyruvic acid and numerous others. Comparatively small amounts of the cobalt catalyst have to be separated off here.
- the invention therefore relates to a process for the pure preparation of N-acetylamino acids and, in particular, of N-acetyl-DL-phenylalanine by removing cobalt carbonyl catalysts from the reaction solution while simultaneously recovering the cobalt contained.
- N-acetyl-aminocarboxylic acids can be prepared in a manner known per se according to DE-OS 23 64 039 by reaction from the corresponding organic halides with hydrogen and carbon monoxide in the presence of cobalt carbonyl catalysts and an amide .
- This procedure requires large amounts of cobalt carbonyl catalysts.
- DE-OS there is no technically usable way of selectively and completely removing the large amounts of the catalyst and of recovering the cobalt.
- the DE-OS does not specify how the acetylamino carboxylic acids are isolated and how they can be separated from the residues of cobalt as required. Accordingly, the method of DE-OS is not usable in the known form.
- the task was to isolate carboxylic acids from their reaction solutions with contents of cobalt carbonyl catalysts and, if possible, to remove residues of cobalt compounds and to recover the cobalt contained in the cobalt carbonyl catalysts in a form which enables the cobalt to be reused .
- the task was to present N-acetyl- ⁇ -aminocarboxylic acids and especially N-acetyl-DL-phenylalanine from their reaction solutions with contents of cobalt carbonyl catalysts in pure form and with the lowest possible losses, and to separate the cobalt of the catalyst from the target product, If possible, remove it completely from the reaction solution and isolate it in a recoverable form.
- the target product is preferably precipitated from the resulting aqueous phase by acidification with acids, in particular mineral acids, and isolated by separation.
- the organic phase is expediently distilled.
- the solvents used in particular are made accessible again for the production of the respective carboxylic acid.
- the solvents used in particular are made accessible again for the production of the respective carboxylic acid.
- the carboxylic acid formed in the carbonylation in particular N-acetylaminocarboxylic acids, and of these in particular N-acetyl-DL-phenylalanine, the content of which can be determined analytically in the reaction solution, can be obtained virtually quantitatively by the present process of the pure preparation can.
- the high purity of the target product, in particular N-acetyl-DL-aminocarboxylic acids of 98% or more, is also very remarkable.
- the respective product has practically the theoretical acid number.
- the cobalt can be removed virtually quantitatively as the divalent cobalt salt of the organic acid used for the precipitation from the zero-valent state in the organic phase of the reaction solution or from the (-1) -value state in the aqueous phase.
- Organic carboxylic acids in particular monocarboxylic acids with 1 to 3 C atoms and, of these in particular, the saturated monocarboxylic acids and dicarboxylic acids with 2 to 3 C atoms, in particular the saturated dicarboxylic acids, can be used for the precipitation.
- Formic acid and oxalic acid are preferred.
- Oxalic acid is very preferred.
- the carboxylic acids used for the precipitation should be used in at least an equivalent amount, based on the cobalt of the catalyst, which can be determined by analysis. An excess of up to 20% over the equivalent amount is preferred, preferably an excess of up to 10%.
- the acids used can be added as pure substances in liquid or solid form or as their aqueous solutions. Aqueous solutions are expediently added in the most concentrated form possible. It can be added to the still hot reaction solution.
- the addition will take place at temperatures of 20 to 90 ° C, preferably at 50 to 80 ° C.
- the reaction solution is preferably kept at the addition temperature for up to one hour after the addition of the mono- or dicarboxylic acids.
- alkaline means i.e. by adding alkali metal hydroxide such as NaOH or KOH or alkali metal carbonates such as sodium carbonate, sodium bicarbonate or potassium carbonate or by adding calcium hydroxide, preferably in concentrated aqueous solution, the reaction solution to pH values between 5.8 and 8, preferably 6.8 to 7.2, set.
- alkali metal hydroxide such as NaOH or KOH
- alkali metal carbonates such as sodium carbonate, sodium bicarbonate or potassium carbonate
- calcium hydroxide preferably in concentrated aqueous solution
- the precipitated cobalt salt of the mono- or dicarboxylic acid added can then be removed, for example by filtration.
- an aqueous phase is obtained with the salt of the carboxylic acid of the reaction solution, in the case of N-rcetyl- ⁇ -aminocarboxylic acids, the salts thereof, and an organic phase with, in particular, solvents contained in the reaction solution of carbonylation and any by-products that may have formed.
- the separated aqueous phase can now be concentrated Acids, in particular mineral acids, such as hydrochloric acid, sulfuric acid or phosphoric acid, very preferably hydrochloric acid, are added to completely precipitate the carboxylic acid formed by carbonylation. Acidify to pH 1. If necessary, cooling can be carried out with or after adding the mineral acid. it was found that a perfect separation of the carboxylic acid formed by carbo lation is possible.
- N-acetyl-ol-aminocarboxylic acids and, in particular, N-acetyl-DL-phenylalanine can be separated therefrom in high purity and with extremely low cobalt contents and very completely from the aqueous phase with the addition of the acids.
- the yield data relate to the known production process according to DE-OS 23 64 039.
- the carboxylic acids formed are practically 100% recovered by the pure preparation measures according to the invention.
- the precipitated cobalt salts can be converted into the oxides from which the cobalt carbonyl catalysts are produced in a known manner.
- the methyl isobutyl ketone is separated from the separated organic phase by distillation in a purity of over 99% and used again in the reaction.
- Example 2 The reaction according to Example 1 is repeated, but the cobalt of the catalyst is completely precipitated using 1012 g of formic acid instead of oxalic acid. After cooling and drying, 696 g of cobalt formate are obtained. After acidification as in Example 1, but with sulfuric acid, the almost 100% of the determined amount of the target product N-acetyl-phenylalanine.
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- Chemical & Material Sciences (AREA)
- Organic Chemistry (AREA)
- Organic Low-Molecular-Weight Compounds And Preparation Thereof (AREA)
- Low-Molecular Organic Synthesis Reactions Using Catalysts (AREA)
Abstract
Aus Reaktionslösungen von Carbonsäuren, die durch Carbonylierung mit Hilfe von Kobaltcarbonyl-Katalysatoren hergestellt wurden, wird das Kobalt des Katalysators durch Zugabe von mindestens äquivalenten Mengen von Monooder Dicarbonsäuren und Neutralisation mit alkalischen Mitteln als Kobalt-II-Salz der zugegebenen Säure gefällt und die Carbonsäure der Reaktionslösung durch Ansäuern vollständig gewonnen.From reaction solutions of carboxylic acids, which were produced by carbonylation with the aid of cobalt carbonyl catalysts, the cobalt of the catalyst is precipitated by adding at least equivalent amounts of mono or dicarboxylic acids and neutralization with alkaline agents as the cobalt II salt of the added acid and the carboxylic acid Reaction solution completely obtained by acidification.
Description
Die Erfindung betrifft ein Verfahren zur Reindarstellung von Carbonsäuren aus ihren Reaktionslösungen, worin Kobaltcarbonyl-Katalysatoren wie insbesondere Co2(CO)8 oder entsprechende ionische Kobaltcarbonylverbindungen enthalten sind. Solche Kobaltcarbonyl-Katalysatoren enthalten den wertvollen Rohstoff Kobalt, der nach Möglichkeit wiedergewonnen werden soll. Weiterhin erschweren die Kobalt-Katalysatoren die Reindarstellung der Carbon säuren und bilden Verunreinigen in den Zielprodukten. Nach bekannten Verfahren der Carbonylierung mit Hilfe von Kobaltcarbonyl-Katalysatoren, insbesondere Dikobaltoctacarbonyl, können eine Reihe von Carbonsäuren durch Einfügung von einem oder ggf. zwei Molekülen CO und ggf. weiteren Molekülteilen hergestellt werden, wie beispielsweise Arylessigsäuren, besonders Phenylessigsäure, Malonsäure und deren Ester, Phenylbrenztraubensäure und zahlreiche weitere. Hierbei sind vergleichsweise geringe Mengen des Kobalt-Katalysators abzutrennen.The invention relates to a process for the pure preparation of carboxylic acids from their reaction solutions, in which cobalt carbonyl catalysts such as in particular Co 2 (CO) 8 or corresponding ionic cobalt carbonyl compounds are contained. Such cobalt carbonyl catalysts contain the valuable raw material cobalt, which should be recovered if possible. Furthermore, the cobalt catalysts complicate the purification of the carboxylic acids and form contaminants in the target products. According to known carbonylation processes with the aid of cobalt carbonyl catalysts, in particular dicobalt octacarbonyl, a number of carboxylic acids can be prepared by inserting one or possibly two molecules of CO and possibly other parts of the molecule, such as arylacetic acids, especially phenylacetic acid, malonic acid and their esters, Phenylpyruvic acid and numerous others. Comparatively small amounts of the cobalt catalyst have to be separated off here.
Im Falle der Herstellung von Acetyl-amino-carbonsäuren, insbesondere N-Acetyl-DL-phenylalanin werden jedoch sehr große Mengen von Koblatcarbonyl-Katalysator benötigt. Insbesondere bezieht sich daher die Erfindung auf ein Verfahren der Reindarstellung von N-Acetyl-aminosäuren sowie unter diesen besonders von N-Acetyl-DL-phenylalanin durch Entfernung von Kobaltcarbonyl-Katalysatoren aus der Reaktionslösung unter gleichzeitiger Gewinnung des enthaltenen Kobalts. N-Acetyl-aminocarbonsäuren, besonders N-Acetyl-α-aminncarbansäuren können auf an sich bekannte Weise nach der DE-OS 23 64 039 durch Umsetzung aus den entsprechenden organischen Halogeniden mit Wasserstoff und Kohlenmonoxid in Gegenwart von Kobaltcarbonyl-Katalysatoren und einem Amid hergestellt werden. Bei dieser Verfahrensweise sind große Mengen von Kobaltcarbonyl-Katalysatoren erforderlich. In der DE-OS wird jedoch kein technisch brauchbarer Weg angegeben, wie die großen Mengen des Katalysators selektriv und vollständig entfernt und das Kobalt gewannen wird. Weiterhin gibt die DE-OS nicht an, wie die Acetyl-amino-carbonsäuren isoliert werden und in erforderlicher Weise von den Resten des Kobalts getrennt werden können. Demgemäß ist das Verfahren der DE-OS in der bekannten Form nicht verwertbar.In the case of the production of acetylamino carboxylic acids, especially N-acetyl-DL-phenylalanine, however, very large amounts of coblate carbonyl catalyst are required. In particular, the invention therefore relates to a process for the pure preparation of N-acetylamino acids and, in particular, of N-acetyl-DL-phenylalanine by removing cobalt carbonyl catalysts from the reaction solution while simultaneously recovering the cobalt contained. N-acetyl-aminocarboxylic acids, especially N-acetyl-α-aminocarboxylic acids, can be prepared in a manner known per se according to DE-OS 23 64 039 by reaction from the corresponding organic halides with hydrogen and carbon monoxide in the presence of cobalt carbonyl catalysts and an amide . This procedure requires large amounts of cobalt carbonyl catalysts. In DE-OS, however, there is no technically usable way of selectively and completely removing the large amounts of the catalyst and of recovering the cobalt. Furthermore, the DE-OS does not specify how the acetylamino carboxylic acids are isolated and how they can be separated from the residues of cobalt as required. Accordingly, the method of DE-OS is not usable in the known form.
Es bestand die Aufgabe, Carbonsäuren aus ihren Reaktionslösungen mit Gehalten von Kobaltcarbonyl-Katalysatoren zu isolieren und nach Möglichkeit von Resten von Kobalt-Uerbindungen zu befreien und das in den Kobaltcarbonyl-Katalysatoren enthaltene Kobalt in einer Form zu gewinnen, die eine erneute Uerwendung des Kobalts ermöglicht.The task was to isolate carboxylic acids from their reaction solutions with contents of cobalt carbonyl catalysts and, if possible, to remove residues of cobalt compounds and to recover the cobalt contained in the cobalt carbonyl catalysts in a form which enables the cobalt to be reused .
Insbesondere bestand die Aufgabe darin, N-Acetyl-α-aminocarbonsäuren und von diesen besonders N-Acetyl-DL-phenylalanin aus seinen Reaktionslösungen mit Gehalten von Kobaltcarbonyl-Katalysatoren rein und mit möglichst geringen Verlusten darzustellen sowie das Kobalt des Katalysators vom Zielprodukt zu trennen, aus der Reaktionslösung nach Möglichkeit vollständig zu entfernen und in wiedergewinnbarer Form zu isolieren.In particular, the task was to present N-acetyl-α-aminocarboxylic acids and especially N-acetyl-DL-phenylalanine from their reaction solutions with contents of cobalt carbonyl catalysts in pure form and with the lowest possible losses, and to separate the cobalt of the catalyst from the target product, If possible, remove it completely from the reaction solution and isolate it in a recoverable form.
Diese Aufgabe wird durch die Anforderung höher Reinheit für die Acetyl-aminosäuren erschwert, insbesondere soweit diese für pharmazeutische Zwecke dienen sollen und insbesondere soweit diese als Ausgangsstoffe einer enzymatischen Racenat-Trernnung vorgesehen sind. Weiterhin wird die Aufgabe erschwert durch unvollständige Bildung der N-Acetyl-aminocarbonsäure und hohe Anteile von Nebenprodukten sowie große Mengen Chloriden in der Reaktionslösung.This task is made more difficult by the requirement of higher purity for the acetyl amino acids, especially to the extent these are intended to serve for pharmaceutical purposes and in particular insofar as they are intended as starting materials for enzymatic racenate separation. The task is further complicated by incomplete formation of the N-acetylaminocarboxylic acid and high proportions of by-products and large amounts of chlorides in the reaction solution.
Es wurde gefunden, daß eine hohe Ausbeute und Reinheit der N-Acetyl-aminocarbonsäuren und insbesondere von N-Acetyl-DL-phenylalanin erreicht wird und daß eine Zerstörung und Umwandlung des Kobaltcarbonyl-Katalysators in der Reaktionslösun möglich ist und Kobalt als Salz einer zugegebenen Mono- oder Dicarbonsäure ausgefällt werden kann. Aus der dann entstehenden Lösung des Zielproduktes kann die hergestellte Carbonsäure, insbesondere N-Acetyl- -aminocarbonsäure und vorzugsweise N-Acetyl-DL-phenylalanin in rein Form mit guter Ausbeute gewonnen werden. Hierzu wird vorgeschlagen, das Zielprodukt in seine Salzform mit Basen zu überführen, durch Ansäuern mit konzentrierten Säuren, insbesondere Mineralsäuren, auszufällen und zu isolieren.It has been found that a high yield and purity of the N-acetyl-aminocarboxylic acids and in particular of N-acetyl-DL-phenylalanine is achieved and that the cobalt carbonyl catalyst can be destroyed and converted in the reaction solution and cobalt as the salt of an added mono - or dicarboxylic acid can be precipitated. The carboxylic acid produced, in particular N-acetyl-aminocarboxylic acid and preferably N-acetyl-DL-phenylalanine, can be obtained in pure form with good yield from the solution of the target product which then results. For this purpose, it is proposed to convert the target product into its salt form with bases, to precipitate and isolate it by acidification with concentrated acids, in particular mineral acids.
Gegenstand der Erfindung ist daher ein Verfahren zur Reindarstellung von Carbonsäuren aus Reaktionslösungen mit Gehalten von Kobaltcarbonyl-Katalysatoren, dadurch gekennzeichnet, daß man die Reaktionslösung
- a) mit Monocarbonsäuren mit 1 bis 3 C-Atomen, Dicarbonsäuren mit 2 bis 3 C-Atomen oder deren wässrige Lösungen in mindestens äquivalenter Menge zum Kobalt des Katalysators versetzt
- b) die Reaktionslösung durch Zugabe alkalischer Mittel neutralisiert und das Kobaltsalz der nach a) zugegebenen Säure entfernt, und
- c) die Carbonsäure aus der Reaktionslösung aufarbeitet.
Weiterer Gegenstand der Erfindung ist ein Verfahren zur Aufarbeitung solcher Reaktionslösungen, dadurch gekennzeichnet, daß die organische Phase nach Neutralisation mit alkalischen Mitteln von der wässrigen Phase, welche das Zielprodukt enthält, getrennt wird.The invention therefore relates to a process for the pure preparation of carboxylic acids from reaction solutions containing cobalt carbonyl catalysts, characterized in that the reaction solution
- a) mixed with monocarboxylic acids with 1 to 3 carbon atoms, dicarboxylic acids with 2 to 3 carbon atoms or their aqueous solutions in at least an equivalent amount to the cobalt of the catalyst
- b) the reaction solution is neutralized by adding alkaline agents and the cobalt salt of the acid added according to a) is removed, and
- c) the carboxylic acid is worked up from the reaction solution.
The invention further relates to a process for working up such reaction solutions, characterized in that the organic phase is separated from the aqueous phase which contains the target product after neutralization with alkaline agents.
Vorzugsweise wird dabei aus der entstehenden wässrigen Phase das Zielprodukt durch Ansäuern mit Säuren, insbesondere Mineralsäuren, gefällt und durch Abtrennung isoliert.The target product is preferably precipitated from the resulting aqueous phase by acidification with acids, in particular mineral acids, and isolated by separation.
Weiterhin und vorzugsweise ist es von erheblichem Vorteil, die abgetrennte organische Phase erfindungsgemäß in den Herstellprozeß zurückzuführen. Zweckmäßig wird hierzu die organische Phase destilliert. Hierdurch werden besonders die verwendeten Lösungsmittel erneut der Herstellung der jeweiligen Carbonsäure zugänglich gemacht. Hierdurch werden besonders die verwendeten Lösungsmittel erneut der Herstellung der jeweiligen Carbonsäure zugänglich gemacht.Furthermore, and preferably, it is of considerable advantage to recycle the separated organic phase according to the invention in the manufacturing process. For this purpose, the organic phase is expediently distilled. As a result, the solvents used in particular are made accessible again for the production of the respective carboxylic acid. As a result, the solvents used in particular are made accessible again for the production of the respective carboxylic acid.
Es hat sich gezeigt, daß die bei der Carbonylierung entstandene Carbonsäure, insbesondere N-Acetyl-aminocarbonsäuren und von diesen besonders N-Acetyl-DL-phenylalanin, deren Gehalt analytisch in der Reaktionslösung feststellbar ist, praktisch quantitativ durch das vorliegende Verfahren der Reindarstellung gewonnen werden kann. Sehr bemerkenswert ist weiterhin die hohe Reinheit des Zielprodukts, insbesondere von N-Acetyl-DL-aminocarbonsäuren von 98 % oder mehr. Das jeweilige Produkt hat praktisch die theoretische Säurezahl.It has been shown that the carboxylic acid formed in the carbonylation, in particular N-acetylaminocarboxylic acids, and of these in particular N-acetyl-DL-phenylalanine, the content of which can be determined analytically in the reaction solution, can be obtained virtually quantitatively by the present process of the pure preparation can. The high purity of the target product, in particular N-acetyl-DL-aminocarboxylic acids of 98% or more, is also very remarkable. The respective product has practically the theoretical acid number.
Es wurde überraschend gefunden, daß das Kobalt aus dem nullwertigen Zustand in der organischen Phase der Reaktionslösung bzw. aus dem (-1)-wertigen Zustand in der wässrigen Phase praktisch quantitativ als 2-wertiges Kobaltsalz der zur Fällung verwendeten organischen Säure entfernt werden kann.It has surprisingly been found that the cobalt can be removed virtually quantitatively as the divalent cobalt salt of the organic acid used for the precipitation from the zero-valent state in the organic phase of the reaction solution or from the (-1) -value state in the aqueous phase.
Zur Fällung können organische Carbonsäuren, insbesondere Monocarbonsäuren mit 1 bis 3 C-Atomen und von diesen besonders die gesättigten Monocarbonsäuren sowie Dicarbonsäuren mit 2 bis 3 C-Atomen insbesondere die gesättigten Dicarbonsäuren verwendet werden. Bevorzugt sind Ameisensäure und Oxalsäure. Sehr bevorzugt ist die Oxalsäure.Organic carboxylic acids, in particular monocarboxylic acids with 1 to 3 C atoms and, of these in particular, the saturated monocarboxylic acids and dicarboxylic acids with 2 to 3 C atoms, in particular the saturated dicarboxylic acids, can be used for the precipitation. Formic acid and oxalic acid are preferred. Oxalic acid is very preferred.
Die zur Fällung verwendeten Carbonsäuren sollen in mindestens äquivalenter Menge, bezogen auf das Kobalt des Katalysators, das durch Analysen feststellbar ist, verwendet werden. Zweckmäßig ist ein Überschuß von bis zu 20 % über die äquivalente Menge, bevorzugt ein Überschuß von bis zu 10 %. Die verwendeten Säuren können als reine Stoffe in flüssiger oder fester Form oder als ihre wässrigen Lösungen zugegeben werden. Wässrige Lösungen werden zweckmäßig in möglichst konzentrierter Form zugegeben. Eine Zugabe in die noch heiße Reaktionslösung ist möglich.The carboxylic acids used for the precipitation should be used in at least an equivalent amount, based on the cobalt of the catalyst, which can be determined by analysis. An excess of up to 20% over the equivalent amount is preferred, preferably an excess of up to 10%. The acids used can be added as pure substances in liquid or solid form or as their aqueous solutions. Aqueous solutions are expediently added in the most concentrated form possible. It can be added to the still hot reaction solution.
Im allgemeinen wird die Zugabe bei Temperaturen von 20 bis 90°C, vorzugsweise bei 50 bis 80°C, erfolgen. Vorzugsweise wird die Reaktionslösung nach der Zugabe derMono-oder Dicarbonsäuren auf die Zugabetemperatur bis zu einer Stunde gehalten.In general, the addition will take place at temperatures of 20 to 90 ° C, preferably at 50 to 80 ° C. The reaction solution is preferably kept at the addition temperature for up to one hour after the addition of the mono- or dicarboxylic acids.
Danach wird durch alkalische Mittel, d.h. durch Zugabe von Alkalihydroxyd wie NaOH oder KOH oder Alkalicarbonate wie Natriumcarbonat, Natriumbicarbonat oder Kaliumcarbonat oder durch Zugabe von Calciumhydroxyd, bevorzugt in konzentrierter wässriger Lösung, die Reaktionslösung auf pH-Werte zwischen 5,8 bis 8, vorzugsweise 6,8 bis 7,2, eingestellt. Das ausfallende Kobaltsalz der zugegebenen Mono- oder Dicarbonsäure kann darauf, beispielsweise durch Filtration, entfernt werden.Thereafter, by alkaline means, i.e. by adding alkali metal hydroxide such as NaOH or KOH or alkali metal carbonates such as sodium carbonate, sodium bicarbonate or potassium carbonate or by adding calcium hydroxide, preferably in concentrated aqueous solution, the reaction solution to pH values between 5.8 and 8, preferably 6.8 to 7.2, set. The precipitated cobalt salt of the mono- or dicarboxylic acid added can then be removed, for example by filtration.
Nach der Filtration des Kobaltsalzes erhält man eine wässrige Phase mit dem Salz der Carbonsäure der Reaktionslösung, im Falle von N-Rcetyl-α-aminocarbonsäuren deren Salze,sowie eine organische Phase mit insbesondere darin enthaltenen Lösungsmitteln der Reaktionslösung der Carbonylierung sowie evtl. entstandenen Nebenprodukten.After filtration of the cobalt salt, an aqueous phase is obtained with the salt of the carboxylic acid of the reaction solution, in the case of N-rcetyl-α-aminocarboxylic acids, the salts thereof, and an organic phase with, in particular, solvents contained in the reaction solution of carbonylation and any by-products that may have formed.
Es hat sich gezeigt, daß eine ausgezeichnete Abtrennung des Zielproduktes von den übrigen Stoffen auf diese Weise erreichbar ist.It has been shown that an excellent separation of the target product from the other substances can be achieved in this way.
Die abgetrennte wässrige Phase kann nunmehr mit konzentrierten Säuren, insbesondere Mineralsäuren, wie Salzsäure, Schwefelsäure oder Phosphorsäure, sehr bevorzugt Salzsäure, zur vollständi gen Ausfällung der durch Carbonylierung entstandenen CarbonsäurE versetzt werden. Hierbei ist auf pH 1 anzusäuern. Wenn erfnrder lich kann bei oder nach Zusatz der Mineralsäure gekühlt werden. es zeigte sich, daß eine einwandfreie Abtrennung der durch Carbo lierung entstandenen Carbonsäure möglich ist. Insbesondere sind N-Acetyl-ol-aminocarbonsäuren und von diesen insbesondere N-Acetyl-DL-phenylalanin in hoher Reinheit und mit außerordentlich geringen Kobaltgehalten sowie sehr vollständig aus der wässrigen Phase mit Zugabe der Säuren abtrennbar.The separated aqueous phase can now be concentrated Acids, in particular mineral acids, such as hydrochloric acid, sulfuric acid or phosphoric acid, very preferably hydrochloric acid, are added to completely precipitate the carboxylic acid formed by carbonylation. Acidify to pH 1. If necessary, cooling can be carried out with or after adding the mineral acid. it was found that a perfect separation of the carboxylic acid formed by carbo lation is possible. In particular, N-acetyl-ol-aminocarboxylic acids and, in particular, N-acetyl-DL-phenylalanine can be separated therefrom in high purity and with extremely low cobalt contents and very completely from the aqueous phase with the addition of the acids.
In den nachfolgenden Beispielen beziehen sich die Angaben der Ausbeute auf den bekannten Herstellprozeß nach DE-OS 23 64 039. Durch die erfindungsgemäßen Maßnahmen der Reindarstellung werden die gebildeten Carbonsäuren praktisch zu 100 % gewonnen. Die gefällten Kobaltsalze können in die Oxide überführt werden, aus denen in bekannter Weise die Kobaltcarbonyl-Katalysatoren hergestellt werden.In the examples below, the yield data relate to the known production process according to DE-OS 23 64 039. The carboxylic acids formed are practically 100% recovered by the pure preparation measures according to the invention. The precipitated cobalt salts can be converted into the oxides from which the cobalt carbonyl catalysts are produced in a known manner.
In einem mit einem Rührer versehenen Druckautoklaven werden 3,5 kg Benzylchlorid, 2,16 kg Acetamid, 1,72 kg Natriumhydrogencarbonat, 4 Liter Wasser, 4 Liter Methylisobutylketon und 8 kg einer 13 Gew.-%igen Lösung von Dikobaltoctacarbonyl in Methylisobutylketon eingefüllt. Nach Zugabe eines Gemisches von CO und H2 (Volumenverhältnis 1:1)bis zu einem Druck von 180 bar wird auf 110 °C aufgeheizt. Ab einer Temperatur von 80°C findet eine rasche Aufnahme statt. Sobald kein Druckabfall mehr eintritt, wird abgekühlt und der restliche CO/H2 abgeblasen. Die Reaktionsmischung wird mit 0,95 kg Oxalsäure, gelöst in 10 1 Wasser, bei 80 °C versetzt. Nach einer Stunde wird die Suspension gekühlt und mit einer 50 Gew.-%igen Natronlauge neutralisiert (pH 7,0).3.5 kg of benzyl chloride, 2.16 kg of acetamide, 1.72 kg of sodium bicarbonate, 4 liters of water, 4 liters of methyl isobutyl ketone and 8 kg of a 13% by weight solution of dicobalt octacarbonyl in methyl isobutyl ketone are introduced into a pressure autoclave equipped with a stirrer. After adding a mixture of CO and H 2 (volume ratio 1: 1) up to a pressure of 180 bar, the mixture is heated to 110 ° C. From a temperature of 80 ° C, a quick absorption takes place. As soon as there is no more pressure drop, the mixture is cooled and the remaining CO / H2 is blown off. The reaction mixture is mixed with 0.95 kg of oxalic acid, dissolved in 10 l of water, at 80.degree. After one hour the suspension is cooled and neutralized with a 50% by weight sodium hydroxide solution (pH 7.0).
Nach der Filtration und Trocknung erhält man 1,1 kg Kobaltoxalat. Aus dem Filtrat wird anschließend die wässrige Phase getrennt und mit konzentrierter HCl bei einer Temperatur zwischen 50 - 80 °C bis pH1 versetzt. Nach dem Abkühlen, Filtration und Trocknung, erhält man 3,7 kg N-Acetyl-phenylalanin.After filtration and drying, 1.1 kg of cobalt oxalate are obtained. The aqueous phase is then separated from the filtrate and mixed with concentrated HCl at a temperature between 50-80 ° C. to pH1. After cooling, filtration and drying, 3.7 kg of N-acetylphenylalanine are obtained.
GC Reinheit ca. 98 % Kobaltgehalt 40 ppm Ausbeute 66,5 %, d.h. praktisch 100% des gebildeten Acetyl-phenylalanins.GC purity approx. 98% cobalt content 40 ppm yield 66.5%, i.e. practically 100% of the acetyl-phenylalanine formed.
Aus der abgetrennten organischen Phase wird das Methylisobutylketon durch Destillation in einer Reinheit von über 99 % abgetrennt und bei der Reaktion wieder eingesetzt.The methyl isobutyl ketone is separated from the separated organic phase by distillation in a purity of over 99% and used again in the reaction.
Die Reaktion nach Beispiel 1 wird wiederholt, jedoch wird das Kobalt des Katalysators unter Uerwendung von 1012 g Ameisensäure, anstelle von Oxalsäure, vollständig gefällt. Nach Abkühlen und Trocknung erhält man 696 g Kobaltformiat. Nach Ansäuern wie im Beispiel 1, jedoch mit Schwefelsäure, wird die festgestellte Menge des Zielprodukts N-Acetyl-phenylalanin zu fast 100 % erhalten.The reaction according to Example 1 is repeated, but the cobalt of the catalyst is completely precipitated using 1012 g of formic acid instead of oxalic acid. After cooling and drying, 696 g of cobalt formate are obtained. After acidification as in Example 1, but with sulfuric acid, the almost 100% of the determined amount of the target product N-acetyl-phenylalanine.
Analog Beispiel 1, jedoch unter Zugabe von folgenden Basen bis zu einem pH-Wert von 7,0
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DE19833345411 DE3345411A1 (en) | 1983-12-15 | 1983-12-15 | METHOD FOR REPRESENTING CARBONIC ACIDS |
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EP (1) | EP0145980A3 (en) |
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DE19545641A1 (en) * | 1995-12-07 | 1997-06-12 | Hoechst Ag | Process for the recovery of cobalt carbonyl catalysts used in the production of N-acyl-alpha-amino acid derivatives by amidocarbonylation |
DE19650501A1 (en) * | 1996-12-05 | 1998-06-10 | Hoechst Ag | Process for the recovery of cobalt carbonyl catalysts used in the production of N-acyl-alpha-amino acid derivatives by amidocarbonylation |
US5750772A (en) * | 1997-01-30 | 1998-05-12 | E. I. Du Pont De Nemours And Company | Decolorization of hydroxy-containing methacrylate homopolymers and copolymers |
US6670505B1 (en) | 2000-03-07 | 2003-12-30 | Eastman Chemical Company | Process for the recovery of organic acids from aqueous solutions |
US6320061B1 (en) | 2000-06-05 | 2001-11-20 | Eastman Chemical Company | Solvent exchange process |
GB0413090D0 (en) * | 2004-06-11 | 2004-07-14 | Degussa | Process for preparing amino acids using the amidocarbonylation reaction (2) |
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GB1414910A (en) * | 1972-12-23 | 1975-11-19 | Ajinomoto Kk | Process for producing aliphatic araliphatic or alicyclic aldehydes and n-carboxylic acyl-a-amino acids |
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US2757204A (en) * | 1951-04-27 | 1956-07-31 | Exxon Research Engineering Co | Acid decobalting of oxo products |
US2757377A (en) * | 1953-03-02 | 1956-07-31 | Exxon Research Engineering Co | Acid decobalting |
US3246024A (en) * | 1962-10-16 | 1966-04-12 | Gulf Research Development Co | Process for converting cobalt compounds to cobalt acetate and/or cobalt propionate |
US3644443A (en) * | 1969-12-08 | 1972-02-22 | Ethyl Corp | Preparation of carboxylic acids |
JPS4817259B1 (en) * | 1970-04-04 | 1973-05-28 | ||
FR2395252A1 (en) * | 1977-06-21 | 1979-01-19 | Inst Francais Du Petrole | PROCESS FOR MANUFACTURING N-ACYL DERIVATIVE OF AMINO ACID |
DE2828041C2 (en) * | 1978-06-26 | 1984-05-10 | Dynamit Nobel Ag, 5210 Troisdorf | Process for the preparation of arylpyruvic acids |
DE3203658C2 (en) * | 1982-02-03 | 1984-09-13 | Dynamit Nobel Ag, 5210 Troisdorf | Process for the production of cobalt and / or manganese oxalate |
DE3204510C2 (en) * | 1982-02-10 | 1986-10-02 | Dynamit Nobel Ag, 5210 Troisdorf | Process for the extraction of cobalt and / or manganese as oxalates |
US4481369A (en) * | 1983-07-28 | 1984-11-06 | Ethyl Corporation | Preparation of α-keto-carboxylic acids from acyl halides |
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1983
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DE3345411C2 (en) | 1988-09-22 |
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US4699999A (en) | 1987-10-13 |
DE3345411A1 (en) | 1985-06-27 |
JPS60156658A (en) | 1985-08-16 |
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